Vulnerability Discussion
Any password, no matter how complex, can eventually be cracked; therefore, passwords need to be changed periodically. If RHEL 9 does not limit the lifetime of passwords and force users to change their passwords, there is the risk that RHEL 9 passwords could be compromised.
Check
Check whether the maximum time period for existing passwords is restricted to 60 days with the following commands:
$ sudo awk -F: '$5 > 60 {print $1 "" "" $5}' /etc/shadow
$ sudo awk -F: '$5 <= 0 {print $1 "" "" $5}' /etc/shadow
If any results are returned that are not associated with a system account, this is a finding.
Fix
Configure noncompliant accounts to enforce a 60-day maximum password lifetime restriction.
passwd -x 60 [user]